Fix python_requires versioning for new setuptools

Newer versions of setuptools will fail to install LNT with the following error: ``` × python setup.py egg_info did not run successfully. │ exit code: 1 ╰─> [1 lines of output] error in LNT setup command: 'python_requires' must be a string containing valid version specifiers; Invalid specifier: '>=3.6.*' [end of output] ``` From reading the documentation, I believe it was a bug to allow >=3.6.* previously, as I don't think wild cards are supported here https://peps.python.org/pep-0345/#requires-python Patch by Justice Adams!

Author: azharudd

setup.py

@@ -138,5 +138,5 @@
 
  ext_modules=[cPerf],
 
- python_requires='>=3.6.*',
+ python_requires='>=3.6',
 )